The present invention generally relates to gaming systems and peripheral devices therefor. More particularly, this invention relates to a headset adapted for use with a gaming system and configured to provide an olfactory stimulation capability.
The experience of virtual reality in computer-based gaming systems depends on the effective representation of sensory modalities. Of the five sensory modalities (sight, hearing, touch, smell, and taste) only two—sight and hearing—are typically addressed in most gaming setups through visual and auditory inputs in the form of a screen display and sound output to speakers or headphones. Smell and taste are absent from most gaming scenarios, and tactile information is generally limited to virtual reality configurations. One multisensory stimulation system incorporating tactile and olfactory stimulation has been described in U.S. Pat. No. 6,702,767 to Douglas et al.
Current gaming setups often employ headsets instead of speaker setups. The advantages of headsets compared to, for example. a surround sound speaker setup, are that there is little or no disturbance of others. Likewise, the cost of a headset is in most cases substantially lower than that of a speaker system of comparable audio quality. Surround sound headphones such as the Zalman Theatre6 six-speaker headphones are generally preferred to simple stereo headphones because they generate better positional audio cues that translate into better survival chances in first-person shooter games. However, a drawback of most headphones is the suppression of background noise, either because of the adaptation to the sound levels of the headphones in “open” headphones or simply because of the shielding or noise suppression accomplished by “closed” headphone designs. On the other hand, unlike the situation of competitive gaming, casual virtual combat or even practice battles do not require complete separation from the environment. Instead, it is often desirable to maintain a certain degree of contact with the outside world. Gaming headphones, therefore, sometimes incorporate additional inputs, for example, for phone or intercom systems that are blended into the audio stream. At the same time, it is possible to port a microphone to the headphones to use the gaming headphones as a headset. Such headsets can be utilized for telephony as well as for communicating messages to opponents in games that are ported to support this option. The positioning of the microphone can either be lateral to the head or, as in aviation headsets, directly in front of the mouth.
Of increasing interest to the gaming industry is the use of olfactory stimuli, that is, the use of smells to create an ultimate gaming sensation. The importance of smell can be appreciated by the fact that the olfactory system is the phylogenetically oldest sensory system, and as such harbors the triggering of primal instincts and emotional reactions beyond anything accomplishable with visual or auditory stimuli. Even though those olfactory stimuli are important, the complexity of the olfactory system and a profound lack of its understanding have been barriers to the commercial realization of a synthetic smell delivery apparatus. Only very recently has some progress has been made, based on the identification and functional classification of four distinct classes of olfactory receptors and some limited understanding of smell decoding.
A fundamental difference between the olfactory and taste systems on one side and the other sensory modalities is that the latter recognize energy in its different manifestations. Hearing uses pressure waves, vision uses light, tactile sensation uses temperature and/or mechanical force. In contrast, taste and smell both entail the recognition of chemical substances within the environment that are binding to either taste buds or olfactory receptors, and possibly the vomeronasal organ (VNO, or Jacobson's organ). Even more complex and less understood is the issue of pheromones, that is, airborne hormones that do not evoke a smell sensation but trigger other physiological responses like arousal, attraction or, on the other end of the scale, deep enmity.
Because the sensation of smell requires the presence of odors in the form of chemical substances that must be inhaled to bind to receptors within the olfactory epithelium of the nasal mucosa, such substances require a mechanism for their release into the air. The amount of air going through the nasal passages is only a minor fraction of the total air volume in the environment of the person playing computer games (from hereon referred to as the “gamer”). Consequently, the amount of odorants or pheromones released into the environment must be large enough so that even the small fraction reaching the nasal receptors will evoke a sensation. In other words, the total amount of odorants needed in any given environment is orders of magnitude higher than that which will eventually reach the targeted olfactory receptors.
Related to the mismatch between total release of odor molecules and those molecules actually smelled is the problem that, even if it is possible to construct an apparatus that generates different odors by mixing known basic ingredients, those components, once released, will linger in the environment until a complete exchange of air has taken place. In other words, when changing a scene in a computer game, the scents from the previous scene will remain if they are released into the environment in a more or less nonspecific way. The consequent mixing of different aromas can create some very confusing and undesirable effects that are preferably avoided. Often, it is in the interest of the gamer that nobody else in his or her environment will be subjected to potentially foul odors, pheromones, or other chemical substances intended exclusively for the gamer's gaming experience.
Several approaches have been suggested in the computer gaming industry to incorporate smells into a multimodal virtual reality sensation. “ismell,” a computer peripheral device developed by DigiScents, Inc., is based on air diffusers that create an aerosol by mixing a number of different aromatic substances to create synthetic odors. The odors are blown in relatively small quantities toward the gamer using a fan. In the interest of keeping contamination of the environment and use of potentially costly supplies as low as possible, the odors were kept at minimal levels, barely reaching the threshold of an olfactory sensation. From a practical standpoint, it is clear that this approach has several drawbacks, particularly the inefficient delivery of the odors to overcome sub-threshold levels, the consequent waste of substances, and contamination of the environment. Moreover, the olfactory system is extremely adaptive and, thus, a slow increase in concentration of any substance may push the recognition threshold to require even higher concentrations of odorants. As a result, different solutions have been sought to overcome these limitations.
More recently, a number of smell generators have been introduced, creating aerosols that are blown in the general direction of the recipient. One such device proposed as an olfactory computer game enhancement is described in U.S. Pat. No. 6,149,873 to Potter et al. In this particular case, as well as in most other cases, a number of substances are mixed in specific ratios to create synthetic odors for the purpose of triggering certain olfactory responses. However, a drawback is the nonspecific release of smells into the environment, which adds cost and risks unpleasant side effects on others sharing the same environment. U.S. Pat. No. 6,994,328 to Watkins et al. is intended to address this concern with the use of a bolus generator that blows scented “smoke rings” of highly concentrated scents at a target. Other approaches are described in U.S. Pat. Nos. 6,169,595 and 6,803,987 to Manne and involve delivering scents to a gamer through a nasal tube, a mask, or a stand, and then using a scent scrubber to clear lingering odors before a new scent is delivered. Another precision scent-delivery system using a nasal tube is disclosed in U.S. Pat. No. 5,610,674 to Martin.